Dream it, Design it, Build it. www.ccee.engineering.iastate.edu
I OWA S TATE U NIVERSITY Civil, Construction & Environmental
Engineering Bradley Fleming, Sri Sritharan, & JinWei Huang Iowa
State University Kanthasamy Muraleetharan & Gerald Miller
Oklahoma University
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1.Finite Element (OpenSees) Detailed 3D analysis Used to
understand complex interactions between pile and improved soil
improved soil and unimproved soil 2.p-y Analysis Method (LPILE)
Simple 2D analysis Attractive for engineers in industry Account for
improved soil of limited width by applying modification factors to
p-y relationships
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Pile (forceBeamColumn) 7.23 m total length 34 beam elements 5.3
m embedded length Non-linear fiber section (half of pile) Soil
Island (OpenSeesPL soil mesh generation) 10.3 m long, 5.15 m wide,
and 7.62 m high 3,450 nodes 2,492 soil elements Soil Contact
Elements (BeamContact3D) Pile r m1 m2 slave P Soil Elements
(SSPbrick) ClaySand
PressureIndependMultiYieldPressureDependMultiYield G max = 3250
kN/m 2G max = 1.0E+5 kN/m 2 c = 30.5 kN/m 2 = 37 deg. sat =1.8
ton/m 3 sat =2.0 ton/m 3 Clay Sand
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Unimproved PileImproved Pile
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Guo and Lee (2001) Attenuation of stresses in soil layer
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R Equivalent rigidity (analogous to AE for axially loaded
member) L eff - Length of uniform soil layer k i Equivalent
stiffness of the p-y curve S - Stiffness of spring Improved
SoilUnimproved Soil
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JinWei Huang (2011)
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Both LPILE and OpenSees closely resembles centrifuge and field
behavior OpenSees is an effective analysis tool but requires
specialized knowledge and involves high computation costs LPILE is
an attractive tool for engineers and has flexibility to modify p-y
curves The proposed method for modifying p-y curves does well in
characterizing the behavior of piles in improved soil of limited
width